refactor: sdrs disk placement for multi-disk vms

Ref: #2448

Signed-off-by: Ryan Johnson <[email protected]>

Author: tenthirtyam

vsphere/internal/helper/storagepod/storage_pod_helper.go

@@ -480,28 +480,33 @@ func virtualDiskFromDeviceConfigSpecForPlacement(spec types.BaseVirtualDeviceCon
 }
 
 func expandVMPodConfigForPlacement(dc []types.BaseVirtualDeviceConfigSpec, pod *object.StoragePod) []types.VmPodConfigForPlacement {
-	var initialVMConfig []types.VmPodConfigForPlacement
+	var diskLocators []types.PodDiskLocator
 
 	for _, deviceConfigSpec := range dc {
 		d, ok := virtualDiskFromDeviceConfigSpecForPlacement(deviceConfigSpec)
 		if !ok {
 			continue
 		}
 
+		diskLocator := types.PodDiskLocator{
+			DiskId:          d.Key,
+			DiskBackingInfo: d.Backing,
+		}
+
+		diskLocators = append(diskLocators, diskLocator)
+	}
+
+	// Only create a config if we have disks to place
+	if len(diskLocators) > 0 {
 		podConfigForPlacement := types.VmPodConfigForPlacement{
 			StoragePod: pod.Reference(),
-			Disk: []types.PodDiskLocator{
-				{
-					DiskId:          d.Key,
-					DiskBackingInfo: d.Backing,
-				},
-			},
+			Disk:       diskLocators,
 		}
 
-		initialVMConfig = append(initialVMConfig, podConfigForPlacement)
+		return []types.VmPodConfigForPlacement{podConfigForPlacement}
 	}
 
-	return initialVMConfig
+	return nil
 }
 
 // IsMember checks to see if a datastore is a member of the datastore cluster